Cancer-Associated LEMS

Cancer-Associated LEMS

Patients with Cancer-Associated Lambert-Eaton myasthenic syndrome (LEMS) frequently have an underlying small cell lung cancer (SCLC) diagnosis

  • Although rare, Cancer-Associated LEMS is the most common condition of its type in people with SCLC
  • LEMS occurs when the immune system mistakenly attacks a part of the nervous system called the neuromuscular junction. This is where the nerve and muscle interact to control movement
  • In Cancer-Associated LEMS, the antibodies produced by the body to fight the cancer also attack the neuromuscular junction, blocking the signals needed for proper muscle function

Signs and Symptoms of Cancer-Associated LEMS

Be on the lookout for the signs and symptoms of Cancer-Associated LEMS, which may be similar to ones you have with your cancer treatment

  • Diagram of body with stars circling head, indicating dizziness
  • Diagram of body with zees around head, indicating fatigue
  • Drooping eyelids, and/or blurred vision
  • Dry mouth, dry eyes, dry skin
  • Difficulty swallowing
  • Arm weakness
  • Diagram of body with a squiggly line in midsection, indicating constipation
  • Diagram of body with warning sign, indicating erectile dysfunction
  • Diagram of body with wavy lines in upper legs, indicating weakness
  • Diagram of body with wavy lines on lower legs, indicating lower leg weakness
  • Dizziness upon standing
  • Fatigue
  • Drooping eyelids, and/or blurred vision
  • Dry mouth, dry eyes, dry skin
  • Difficulty swallowing
  • Arm weakness
  • Constipation
  • Erectile dysfunction
  • Upper leg weakness
  • Lower leg weakness

Patients with Cancer-Associated LEMS may face numerous daily challenges

A panel consisting of 104 patients with Cancer-Associated LEMS described their experiences and the effects on their lives and those around them.

Muscle pain, which may reduce quality of life

Extreme fatigue, which makes it difficult to do day-to-day tasks and climb stairs

Trouble chewing and slurred speech

Vision trouble and dry mouth, which can interfere with everyday activities

Inability to sleep, which also disrupts their family members’ sleep

Difficulty with self-care and heavy reliance on caregiver support

Patient-reported feelings of depression

Diagnosis of Cancer-Associated LEMS may not be happening nearly enough

9 Out Of 10
Cases of Cancer-Associated LEMS May Not Be Diagnosed
? ? ?
That’s why it is important to talk to your doctor if you are experiencing any symptoms of Cancer-Associated LEMS

Testing For Cancer-Associated LEMS


If your doctor suspects Cancer-Associated LEMS, the diagnosis can be confirmed by:

A physical exam

to evaluate your symptoms and test your reflexes

A blood test

to look for certain antibodies called P/Q- and N-type voltage-gated calcium channel (VGCC) antibodies

An electrodiagnostic test

to measure how well your muscles and nerves are communicating

If you suspect you may have the symptoms of Cancer-Associated LEMS, ask your doctor to order the blood test to confirm the diagnosis.

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